For the dinner before your interview, dress business casual or one small step down from this. Jeans are fine, but no t-shirts. Drink some alcohol if you like, but don't overdo it. Watch what you say because even the interns can have some say in the ranking panel in some residency programs. SEND THOSE THANK YOU CARDS ASAP! I know that some programs will meet every few weeks to review the most recent applicants before their impressions slip from memory. Write cards and/or emails. Both are fine. Keep in contact with some nice resident or program director if you are really interested in the program. During the interview, have a talking agenda and make sure that you hit all your points before the 30 minutes is up. Make sure you get a good sense of the resident life before you leave that day. Make sure you trust the program director and the attendings you meet to mold your future career! Jot down notes of proram highlights and oons when you get home. Save money by emailing programs to ask
for residents to house you, and don't feel badly about asking.